https://github.com/mozilla/gecko-dev
Tip revision: a575b06296a820a61b649d345c3da8e3f2fa3d75 authored by B2G Bumper Bot on 11 May 2015, 18:32:27 UTC
Bumping manifests a=b2g-bump
Bumping manifests a=b2g-bump
Tip revision: a575b06
jsweakmap.cpp
/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
* vim: set ts=8 sts=4 et sw=4 tw=99:
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#include "jsweakmap.h"
#include <string.h>
#include "jsapi.h"
#include "jscntxt.h"
#include "jsfriendapi.h"
#include "jsobj.h"
#include "jswrapper.h"
#include "vm/GlobalObject.h"
#include "vm/WeakMapObject.h"
#include "jsobjinlines.h"
using namespace js;
WeakMapBase::WeakMapBase(JSObject* memOf, JSCompartment* c)
: memberOf(memOf),
compartment(c),
next(WeakMapNotInList)
{
JS_ASSERT_IF(memberOf, memberOf->compartment() == c);
}
WeakMapBase::~WeakMapBase()
{
JS_ASSERT(next == WeakMapNotInList);
}
bool
WeakMapBase::markCompartmentIteratively(JSCompartment* c, JSTracer* tracer)
{
bool markedAny = false;
for (WeakMapBase* m = c->gcWeakMapList; m; m = m->next) {
if (m->markIteratively(tracer))
markedAny = true;
}
return markedAny;
}
void
WeakMapBase::sweepCompartment(JSCompartment* c)
{
for (WeakMapBase* m = c->gcWeakMapList; m; m = m->next)
m->sweep();
}
void
WeakMapBase::traceAllMappings(WeakMapTracer* tracer)
{
JSRuntime* rt = tracer->runtime;
for (CompartmentsIter c(rt, SkipAtoms); !c.done(); c.next()) {
for (WeakMapBase* m = c->gcWeakMapList; m; m = m->next)
m->traceMappings(tracer);
}
}
void
WeakMapBase::resetCompartmentWeakMapList(JSCompartment* c)
{
JS_ASSERT(WeakMapNotInList != nullptr);
WeakMapBase* m = c->gcWeakMapList;
c->gcWeakMapList = nullptr;
while (m) {
WeakMapBase* n = m->next;
m->next = WeakMapNotInList;
m = n;
}
}
bool
WeakMapBase::saveCompartmentWeakMapList(JSCompartment* c, WeakMapVector& vector)
{
WeakMapBase* m = c->gcWeakMapList;
while (m) {
if (!vector.append(m))
return false;
m = m->next;
}
return true;
}
void
WeakMapBase::restoreCompartmentWeakMapLists(WeakMapVector& vector)
{
for (WeakMapBase** p = vector.begin(); p != vector.end(); p++) {
WeakMapBase* m = *p;
JS_ASSERT(m->next == WeakMapNotInList);
JSCompartment* c = m->compartment;
m->next = c->gcWeakMapList;
c->gcWeakMapList = m;
}
}
void
WeakMapBase::removeWeakMapFromList(WeakMapBase* weakmap)
{
JSCompartment* c = weakmap->compartment;
for (WeakMapBase** p = &c->gcWeakMapList; *p; p = &(*p)->next) {
if (*p == weakmap) {
*p = (*p)->next;
weakmap->next = WeakMapNotInList;
break;
}
}
}
static JSObject*
GetKeyArg(JSContext* cx, CallArgs& args)
{
if (args[0].isPrimitive()) {
JS_ReportErrorNumber(cx, js_GetErrorMessage, nullptr, JSMSG_NOT_NONNULL_OBJECT);
return nullptr;
}
return &args[0].toObject();
}
MOZ_ALWAYS_INLINE bool
IsWeakMap(HandleValue v)
{
return v.isObject() && v.toObject().is<WeakMapObject>();
}
MOZ_ALWAYS_INLINE bool
WeakMap_has_impl(JSContext* cx, CallArgs args)
{
JS_ASSERT(IsWeakMap(args.thisv()));
if (args.length() < 1) {
JS_ReportErrorNumber(cx, js_GetErrorMessage, nullptr, JSMSG_MORE_ARGS_NEEDED,
"WeakMap.has", "0", "s");
return false;
}
JSObject* key = GetKeyArg(cx, args);
if (!key)
return false;
if (ObjectValueMap* map = args.thisv().toObject().as<WeakMapObject>().getMap()) {
if (map->has(key)) {
args.rval().setBoolean(true);
return true;
}
}
args.rval().setBoolean(false);
return true;
}
static bool
WeakMap_has(JSContext* cx, unsigned argc, Value* vp)
{
CallArgs args = CallArgsFromVp(argc, vp);
return CallNonGenericMethod<IsWeakMap, WeakMap_has_impl>(cx, args);
}
MOZ_ALWAYS_INLINE bool
WeakMap_clear_impl(JSContext* cx, CallArgs args)
{
JS_ASSERT(IsWeakMap(args.thisv()));
// We can't js_delete the weakmap because the data gathered during GC
// is used by the Cycle Collector
if (ObjectValueMap* map = args.thisv().toObject().as<WeakMapObject>().getMap())
map->clear();
args.rval().setUndefined();
return true;
}
static bool
WeakMap_clear(JSContext* cx, unsigned argc, Value* vp)
{
CallArgs args = CallArgsFromVp(argc, vp);
return CallNonGenericMethod<IsWeakMap, WeakMap_clear_impl>(cx, args);
}
MOZ_ALWAYS_INLINE bool
WeakMap_get_impl(JSContext* cx, CallArgs args)
{
JS_ASSERT(IsWeakMap(args.thisv()));
if (args.length() < 1) {
JS_ReportErrorNumber(cx, js_GetErrorMessage, nullptr, JSMSG_MORE_ARGS_NEEDED,
"WeakMap.get", "0", "s");
return false;
}
JSObject* key = GetKeyArg(cx, args);
if (!key)
return false;
if (ObjectValueMap* map = args.thisv().toObject().as<WeakMapObject>().getMap()) {
if (ObjectValueMap::Ptr ptr = map->lookup(key)) {
// Read barrier to prevent an incorrectly gray value from escaping the
// weak map. See the comment before UnmarkGrayChildren in gc/Marking.cpp
ExposeValueToActiveJS(ptr->value().get());
args.rval().set(ptr->value());
return true;
}
}
args.rval().set((args.length() > 1) ? args[1] : UndefinedValue());
return true;
}
static bool
WeakMap_get(JSContext* cx, unsigned argc, Value* vp)
{
CallArgs args = CallArgsFromVp(argc, vp);
return CallNonGenericMethod<IsWeakMap, WeakMap_get_impl>(cx, args);
}
MOZ_ALWAYS_INLINE bool
WeakMap_delete_impl(JSContext* cx, CallArgs args)
{
JS_ASSERT(IsWeakMap(args.thisv()));
if (args.length() < 1) {
JS_ReportErrorNumber(cx, js_GetErrorMessage, nullptr, JSMSG_MORE_ARGS_NEEDED,
"WeakMap.delete", "0", "s");
return false;
}
JSObject* key = GetKeyArg(cx, args);
if (!key)
return false;
if (ObjectValueMap* map = args.thisv().toObject().as<WeakMapObject>().getMap()) {
if (ObjectValueMap::Ptr ptr = map->lookup(key)) {
map->remove(ptr);
args.rval().setBoolean(true);
return true;
}
}
args.rval().setBoolean(false);
return true;
}
static bool
WeakMap_delete(JSContext* cx, unsigned argc, Value* vp)
{
CallArgs args = CallArgsFromVp(argc, vp);
return CallNonGenericMethod<IsWeakMap, WeakMap_delete_impl>(cx, args);
}
static bool
TryPreserveReflector(JSContext* cx, HandleObject obj)
{
if (obj->getClass()->ext.isWrappedNative ||
(obj->getClass()->flags & JSCLASS_IS_DOMJSCLASS) ||
(obj->is<ProxyObject>() &&
obj->as<ProxyObject>().handler()->family() == GetDOMProxyHandlerFamily()))
{
JS_ASSERT(cx->runtime()->preserveWrapperCallback);
if (!cx->runtime()->preserveWrapperCallback(cx, obj)) {
JS_ReportErrorNumber(cx, js_GetErrorMessage, nullptr, JSMSG_BAD_WEAKMAP_KEY);
return false;
}
}
return true;
}
static inline void
WeakMapPostWriteBarrier(JSRuntime* rt, ObjectValueMap* weakMap, JSObject* key)
{
#ifdef JSGC_GENERATIONAL
/*
* Strip the barriers from the type before inserting into the store buffer.
* This will automatically ensure that barriers do not fire during GC.
*
* Some compilers complain about instantiating the WeakMap class for
* unbarriered type arguments, so we cast to a HashMap instead. Because of
* WeakMap's multiple inheritace, We need to do this in two stages, first to
* the HashMap base class and then to the unbarriered version.
*/
ObjectValueMap::Base* baseHashMap = static_cast<ObjectValueMap::Base*>(weakMap);
typedef HashMap<JSObject*, Value> UnbarrieredMap;
UnbarrieredMap* unbarrieredMap = reinterpret_cast<UnbarrieredMap*>(baseHashMap);
typedef gc::HashKeyRef<UnbarrieredMap, JSObject*> Ref;
if (key && IsInsideNursery(rt, key))
rt->gcStoreBuffer.putGeneric(Ref((unbarrieredMap), key));
#endif
}
MOZ_ALWAYS_INLINE bool
WeakMap_set_impl(JSContext* cx, CallArgs args)
{
JS_ASSERT(IsWeakMap(args.thisv()));
if (args.length() < 1) {
JS_ReportErrorNumber(cx, js_GetErrorMessage, nullptr, JSMSG_MORE_ARGS_NEEDED,
"WeakMap.set", "0", "s");
return false;
}
RootedObject key(cx, GetKeyArg(cx, args));
if (!key)
return false;
RootedValue value(cx, (args.length() > 1) ? args[1] : UndefinedValue());
Rooted<JSObject*> thisObj(cx, &args.thisv().toObject());
ObjectValueMap* map = thisObj->as<WeakMapObject>().getMap();
if (!map) {
map = cx->new_<ObjectValueMap>(cx, thisObj.get());
if (!map->init()) {
js_delete(map);
JS_ReportOutOfMemory(cx);
return false;
}
thisObj->setPrivate(map);
}
// Preserve wrapped native keys to prevent wrapper optimization.
if (!TryPreserveReflector(cx, key))
return false;
if (JSWeakmapKeyDelegateOp op = key->getClass()->ext.weakmapKeyDelegateOp) {
RootedObject delegate(cx, op(key));
if (delegate && !TryPreserveReflector(cx, delegate))
return false;
}
JS_ASSERT(key->compartment() == thisObj->compartment());
JS_ASSERT_IF(value.isObject(), value.toObject().compartment() == thisObj->compartment());
if (!map->put(key, value)) {
JS_ReportOutOfMemory(cx);
return false;
}
WeakMapPostWriteBarrier(cx->runtime(), map, key.get());
args.rval().setUndefined();
return true;
}
static bool
WeakMap_set(JSContext* cx, unsigned argc, Value* vp)
{
CallArgs args = CallArgsFromVp(argc, vp);
return CallNonGenericMethod<IsWeakMap, WeakMap_set_impl>(cx, args);
}
JS_FRIEND_API(bool)
JS_NondeterministicGetWeakMapKeys(JSContext* cx, JSObject* objArg, JSObject** ret)
{
RootedObject obj(cx, objArg);
obj = UncheckedUnwrap(obj);
if (!obj || !obj->is<WeakMapObject>()) {
*ret = nullptr;
return true;
}
RootedObject arr(cx, NewDenseEmptyArray(cx));
if (!arr)
return false;
ObjectValueMap* map = obj->as<WeakMapObject>().getMap();
if (map) {
// Prevent GC from mutating the weakmap while iterating.
gc::AutoSuppressGC suppress(cx);
for (ObjectValueMap::Base::Range r = map->all(); !r.empty(); r.popFront()) {
RootedObject key(cx, r.front().key());
if (!cx->compartment()->wrap(cx, &key))
return false;
if (!NewbornArrayPush(cx, arr, ObjectValue(*key)))
return false;
}
}
*ret = arr;
return true;
}
static void
WeakMap_mark(JSTracer* trc, JSObject* obj)
{
if (ObjectValueMap* map = obj->as<WeakMapObject>().getMap())
map->trace(trc);
}
static void
WeakMap_finalize(FreeOp* fop, JSObject* obj)
{
if (ObjectValueMap* map = obj->as<WeakMapObject>().getMap()) {
map->check();
#ifdef DEBUG
map->~ObjectValueMap();
memset(static_cast<void*>(map), 0xdc, sizeof(*map));
fop->free_(map);
#else
fop->delete_(map);
#endif
}
}
static bool
WeakMap_construct(JSContext* cx, unsigned argc, Value* vp)
{
JSObject* obj = NewBuiltinClassInstance(cx, &WeakMapObject::class_);
if (!obj)
return false;
vp->setObject(*obj);
return true;
}
const Class WeakMapObject::class_ = {
"WeakMap",
JSCLASS_HAS_PRIVATE | JSCLASS_IMPLEMENTS_BARRIERS |
JSCLASS_HAS_CACHED_PROTO(JSProto_WeakMap),
JS_PropertyStub, /* addProperty */
JS_DeletePropertyStub, /* delProperty */
JS_PropertyStub, /* getProperty */
JS_StrictPropertyStub, /* setProperty */
JS_EnumerateStub,
JS_ResolveStub,
JS_ConvertStub,
WeakMap_finalize,
nullptr, /* call */
nullptr, /* construct */
nullptr, /* xdrObject */
WeakMap_mark
};
static const JSFunctionSpec weak_map_methods[] = {
JS_FN("has", WeakMap_has, 1, 0),
JS_FN("get", WeakMap_get, 2, 0),
JS_FN("delete", WeakMap_delete, 1, 0),
JS_FN("set", WeakMap_set, 2, 0),
JS_FN("clear", WeakMap_clear, 0, 0),
JS_FS_END
};
JSObject*
js_InitWeakMapClass(JSContext* cx, HandleObject obj)
{
JS_ASSERT(obj->isNative());
Rooted<GlobalObject*> global(cx, &obj->as<GlobalObject>());
RootedObject weakMapProto(cx, global->createBlankPrototype(cx, &WeakMapObject::class_));
if (!weakMapProto)
return nullptr;
RootedFunction ctor(cx, global->createConstructor(cx, WeakMap_construct,
cx->names().WeakMap, 0));
if (!ctor)
return nullptr;
if (!LinkConstructorAndPrototype(cx, ctor, weakMapProto))
return nullptr;
if (!DefinePropertiesAndBrand(cx, weakMapProto, nullptr, weak_map_methods))
return nullptr;
if (!GlobalObject::initBuiltinConstructor(cx, global, JSProto_WeakMap, ctor, weakMapProto))
return nullptr;
return weakMapProto;
}